package com.wyy.image;

import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

import javax.imageio.ImageIO;

import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGEncodeParam;
import com.sun.image.codec.jpeg.JPEGImageEncoder; 

public class ImageCompressUtil {
    /** 
     * 直接指定压缩后的宽高： 
     * (先保存原文件，再压缩、上传) 
     * 壹拍项目中用于二维码压缩 
     * @param oldFile 要进行压缩的文件全路径 
     * @param width 压缩后的宽度 
     * @param height 压缩后的高度 
     * @param quality 压缩质量 
     * @param smallIcon 文件名的小小后缀(注意，非文件后缀名称),入压缩文件名是yasuo.jpg,则压缩后文件名是yasuo(+smallIcon).jpg 
     * @return 返回压缩后的文件的全路径 
     */  
    public static String zipImageFile(String oldFile, int width, int height,  
            float quality, String smallIcon) {  
        if (oldFile == null) {  
            return null;  
        }  
        String newImage = null;  
        try {  
            /**对服务器上的临时文件进行处理 */  
            Image srcFile = ImageIO.read(new File(oldFile));  
            /** 宽,高设定 */  
            BufferedImage tag = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);  
            tag.getGraphics().drawImage(srcFile, 0, 0, width, height, null);  
            String filePrex = oldFile.substring(0, oldFile.indexOf('.'));  
            /** 压缩后的文件名 */  
            newImage = filePrex + smallIcon + oldFile.substring(filePrex.length());  
            /** 压缩之后临时存放位置 */  
            FileOutputStream out = new FileOutputStream(newImage);  
            JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);  
            JPEGEncodeParam jep = JPEGCodec.getDefaultJPEGEncodeParam(tag);  
            /** 压缩质量 */  
            jep.setQuality(quality, true);  
            encoder.encode(tag, jep);  
            out.close();  
        } catch (FileNotFoundException e) {  
            e.printStackTrace();  
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
        return newImage;  
    }  
  
    /** 
     * 保存文件到服务器临时路径(用于文件上传) 
     * @param fileName 
     * @param is 
     * @return 文件全路径 
     */  
    public static String writeFile(String fileName, InputStream is) {  
        if (fileName == null || fileName.trim().length() == 0) {  
            return null;  
        }  
        try {  
            /** 首先保存到临时文件 */  
            FileOutputStream fos = new FileOutputStream(fileName);  
            byte[] readBytes = new byte[512];// 缓冲大小  
            int readed = 0;  
            while ((readed = is.read(readBytes)) > 0) {  
                fos.write(readBytes, 0, readed);  
            }  
            fos.close();  
            is.close();  
        } catch (FileNotFoundException e) {  
            e.printStackTrace();  
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
        return fileName;  
    }  
  
    /** 
     * 等比例压缩算法：  
     * 算法思想：根据压缩基数和压缩比来压缩原图，生产一张图片效果最接近原图的缩略图 
     * @param srcURL 原图地址 
     * @param deskURL 缩略图地址 
     * @param comBase 压缩基数 
     * @param scale 压缩限制(宽/高)比例  一般用1： 
     * 当scale>=1,缩略图height=comBase,width按原图宽高比例;若scale<1,缩略图width=comBase,height按原图宽高比例 
     * @throws Exception 
     * @author shenbin 
     * @createTime 2014-12-16 
     * @lastModifyTime 2014-12-16 
     */  
    public static void saveMinPhoto(String srcURL, String deskURL, double comBase,  
            double scale) throws Exception {  
        File srcFile = new java.io.File(srcURL);  
        Image src = ImageIO.read(srcFile);  
        int srcHeight = src.getHeight(null);  
        int srcWidth = src.getWidth(null);  
        int deskHeight = 0;// 缩略图高  
        int deskWidth = 0;// 缩略图宽  
        double srcScale = (double) srcHeight / srcWidth;  
        /**缩略图宽高算法*/  
        if ((double) srcHeight > comBase || (double) srcWidth > comBase) {  
            if (srcScale >= scale || 1 / srcScale > scale) {  
                if (srcScale >= scale) {  
                    deskHeight = (int) comBase;  
                    deskWidth = srcWidth * deskHeight / srcHeight;  
                } else {  
                    deskWidth = (int) comBase;  
                    deskHeight = srcHeight * deskWidth / srcWidth;  
                }  
            } else {  
                if ((double) srcHeight > comBase) {  
                    deskHeight = (int) comBase;  
                    deskWidth = srcWidth * deskHeight / srcHeight;  
                } else {  
                    deskWidth = (int) comBase;  
                    deskHeight = srcHeight * deskWidth / srcWidth;  
                }  
            }  
        } else {  
            deskHeight = srcHeight;  
            deskWidth = srcWidth;  
        }  
        BufferedImage tag = new BufferedImage(deskWidth, deskHeight, BufferedImage.TYPE_3BYTE_BGR);  
        tag.getGraphics().drawImage(src, 0, 0, deskWidth, deskHeight, null); //绘制缩小后的图  
        FileOutputStream deskImage = new FileOutputStream(deskURL); //输出到文件流  
        JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(deskImage);  
        encoder.encode(tag); //近JPEG编码  
        deskImage.close();  
    }  
  
    public static void main(String args[]) throws Exception {  
//        ImageCompressUtil.zipImageFile("f:/食尸鬼 - 藿香.jpg", 1280, 1280, 1f, "x2");  
//        ImageCompressUtil.saveMinPhoto("f:/食尸鬼 - 藿香.jpg", "f:/11.jpg", 139, 0.9d);  
//        ImageCompressUtil.saveMinPhoto("E:/P70305-153227.jpg", "E:/11.jpg", 139, 0.9d);
//        ImageCompressUtil.saveMinPhoto("E:/P70305-153227.jpg", "E:/11.jpg", 139, 0.9d);
        ImageCompressUtil.saveMinPhoto("E:/P70305-153227.jpg", "E:/11.jpg", 600, 2d);
    }  
}
